Native to: sub-Saharan Africa
 
   
Introduced to: American Southwest
Mode of transportation: A single cargo ship traveling from the Black Sea to the Great Lakes introduced the mussels to the U.S. The mussels spread quickly because, during the larval stage, they drift on currents, often traveling quite far! The mussels can also attach to boats to expand their range.
 
   
 

Bluntly put, these thumb-sized mussels clog things up! They are famous for getting into the water intake systems of boats, power plants and water treatment facilities and reducing water flow. This clogging costs millions of dollars to fix!

Zebra mussels are voracious plankton eaters, removing vast amounts of food from the water. When plankton is removed from the water, more sunshine reaches the river’s bottom, encouraging too much plant growth. The small fish that eat plankton have less to eat and their numbers go down. Also, the larger fish that feed on the small ones may die for lack of food. Finally, the Zebra Mussels take food, space, and oxygen, causing the death of native mussel species.
 
     
 
    One female zebra mussel can produce between 30,000 and 1,000,000 eggs each year!